diff --git a/bar.go b/bar.go
index b6257be..e834a21 100644
--- a/bar.go
+++ b/bar.go
@@ -323,15 +323,12 @@
 // if you need to adjust start time of all average based decorators
 // or after progress resume.
 func (b *Bar) DecoratorAverageAdjust(start time.Time) {
-	result := make(chan *sync.WaitGroup)
-	select {
-	case b.operateState <- func(s *bState) {
-		var wg sync.WaitGroup
-		s.decoratorAverageAdjust(start, &wg)
-		result <- &wg
-	}:
-		wg := <-result
-		wg.Wait()
+	select {
+	case b.operateState <- func(s *bState) {
+		for _, d := range s.averageDecorators {
+			d.AverageAdjust(start)
+		}
+	}:
 	case <-b.ctx.Done():
 	}
 }
@@ -591,17 +588,6 @@
 	}
 }
 
-func (s bState) decoratorAverageAdjust(start time.Time, wg *sync.WaitGroup) {
-	wg.Add(len(s.averageDecorators))
-	for _, d := range s.averageDecorators {
-		d := d
-		go func() {
-			d.AverageAdjust(start)
-			wg.Done()
-		}()
-	}
-}
-
 func (s bState) decoratorShutdownNotify(wg *sync.WaitGroup) {
 	wg.Add(len(s.shutdownListeners))
 	for _, d := range s.shutdownListeners {